Exposure to low-dose ionizing radiation increases risk of cardiovascular death, a study published in 2009 in International Journal of Occupational Medicine and Environmental Health suggests.
Ionizing radiation such as x-ray used in medical diagnostic tools and cancer treatment has already been known to boost cancer risk. But the cardiovascular risk from ionizing radiation is not as widely publicized as its cancer risk.
Most patients have little or no awareness of the dangers of ionizing radiation due to medical imaging scans. Moreover, few doctors realize that one CT scan exposes the body to the equivalent of several hundred X-rays. Very few women undergoing mammograms understand that the the radiation emitted by mammography machines actually causes cancer by exposing heart and breast tissue to dangerous ionizing radiation that directly causes DNA damage.
A routine mammogram screening typically involves four x-rays, two per breast. This amounts to more than 150 times the amount of radiation that is used for a single chest x-ray. Bottom line: screening mammograms send a strong dose of ionizing radiation through your tissues. Any dose of ionzing radiation is capable of contributing to cancer and heart disease.
What's Your Radiation Dose?
The study led by Zielinski J.M. and colleagues of Health Canada in Ottawa, Canada found those who were occupationally exposed to ionizing radiation such as employees at nuclear power stations, medical, dental, and industrial workers were more likely to die of cardiovascular disease than those in the general population in Canada.
The study involved 337,397 individuals who were occupationally exposed to ionizing radiation and included in the National Dose Registry of Canada.
Radiation exposure is measured in doses, taking into account both internal and external exposure to ionizing radiation, which includes gamma, beta and X-rays. The amount of radiation absorbed by a gram of tissue is expressed in millisieverts, or mSv.
During the study period between 1951 and 1995, 3533 deaths from cardiovascular diseases have been recorded.
Those who were exposed to higher cumulative doses of ionizing radiation were found more likely to die from cardiovascular disease.
Their risk of dying from cardiovascular disease was even higher than those reported in the studies of Japanese atomic bomb survivors.
"The study has demonstrated a strong positive association between radiation dose and the risk of CVD mortality. Caution needs to be exercised when interpreting these results, due to the potential bias introduced by dosimetry uncertainties, the possible record linkage errors, and especially by the lack of adjustment for non-radiation risk factors." the researchers concluded.